K20D light metering issue

xjjohnno · 05-10-2009, 02:14 AM

A weird and annoying behaviour performed by the camera today was some seriously out of whack light metering that killed some interesting pics due to severe over exposures. For some weird reason the camera eventually decided to behave itself. On looking at the exif I was getting pictures taken at around 1/125 in strong sunlight where I'd normally expect up to 1/4000. The lens in use was a Pentax DA 55-300mm. Granted I'd been slack about resetting the camera to P mode after some manual lens usage at TAV mode but considering I'd been using the same lens the day before without problems I somehow doubt that was the issue. No settings have been changed recently so not an issue of the idiot in control of the camera ere. Any ideas on what might have been causing the problem or am I looking at playing the role of irate customer and putting in a warranty claim?

Edvinas · 05-10-2009, 02:49 AM

Show us some problematic pictures with intact EXIF info.

Otherwise it is impossible to tell something.

5teve · 05-10-2009, 04:01 AM

Originally Posted by xjjohnno

A weird and annoying behaviour performed by the camera today was some seriously out of whack light metering that killed some interesting pics due to severe over exposures. For some weird reason the camera eventually decided to behave itself. On looking at the exif I was getting pictures taken at around 1/125 in strong sunlight where I'd normally expect up to 1/4000. The lens in use was a Pentax DA 55-300mm. Granted I'd been slack about resetting the camera to P mode after some manual lens usage at TAV mode but considering I'd been using the same lens the day before without problems I somehow doubt that was the issue. No settings have been changed recently so not an issue of the idiot in control of the camera ere. Any ideas on what might have been causing the problem or am I looking at playing the role of irate customer and putting in a warranty claim?

are you using a split prism screen? or spot metering? im suffering similar issues!

Thanks

Steve

xjjohnno · 05-10-2009, 04:56 AM

Using spot metering Steve centre weighted. Samples are no longer available as after looking into their properties I dumped them.. Most likely scenario I'm afraid might be the idiot behind the camera as I probably inadvertently set the wheel for shutter speed rate rate. The shutter speeds were all at 1/125 sec as a constant which would suggest that I'd moved the wheel to control that without knowing I'd done so as auto metering would have set different shutter speeds to match a variety of differing conditions.

defiant · 05-10-2009, 10:35 PM

Originally Posted by xjjohnno

Most likely scenario I'm afraid might be the idiot behind the camera as I probably inadvertently set the wheel for shutter speed rate rate. The shutter speeds were all at 1/125 sec as a constant which would suggest that I'd moved the wheel to control that without knowing I'd done so as auto metering would have set different shutter speeds to match a variety of differing conditions.

There's a setting that allows the camera to temporarily auto-adjust the shutter speed in Tv mode, if exposure cannot be met on current settings. From memory it's custom setting 10 - auto exposure compensation. I turn it on as a safeguard, in case i need to make a rapid shot without having time to check or change settings, or even if i forget that i'm on wrong settings

*Wheatfield* · 05-11-2009, 07:46 PM

Originally Posted by xjjohnno

Using spot metering Steve centre weighted.

Were you using spot or center weighted? Your post doesn't specify.
If you were using spot metering and not compensating each and every exposure to take the reflectivity of what was in the metering zone into account, your exposures would be completely whacked.
I still question the wisdom of putting spot metering onto a DSLR, but apparently I'm in a minority.
However, if you don't know what a spot meter does, and if you don't know how to use a spot meter, you are pretty much guaranteed to get bad exposures with spot metering.

xjjohnno · 05-11-2009, 10:04 PM

Probably phrased it wrong, centre weighted metering was the metering setting. Pics that went silly were not likely to be affected by reflections. A picture of a kite, blue sky back ground, a bird foraging in the grass with dried grass and earth with the final set of pictures being an air ambulance taking off with a building and then the sky as the back ground. Metering issues would have been noticed straight away if I'd been keeping an eye on the shutter speeds read out in the view finder.